<nav class="navbar navbar-expand-md bg-dark navbar-dark">
  <!-- Brand -->
  <a class="navbar-brand" href="#">
    <img src="https://img1.baidu.com/it/u=2544257883,100398830&fm=253&fmt=auto&app=138&f=JPEG?w=500&h=500" alt="logo" style="width:40px; margin-left: 15px">
  </a>

  <!-- Toggler/collapsibe Button -->
  <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#collapsibleNavbar">
    <span class="navbar-toggler-icon"></span>
  </button>

  <!-- Navbar links -->
  <div class="collapse navbar-collapse" id="collapsibleNavbar">
    <ul class="navbar-nav">
      <li class="nav-item">
        <a class="nav-link" href="#">Link</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Link</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Link</a>
      </li>
      <!-- Dropdown -->
      <li class="nav-item dropdown">
        <a class="nav-link dropdown-toggle" href="#" id="navbardrop" data-bs-toggle="dropdown">
          Dropdown link
        </a>
        <div class="dropdown-menu">
          <a class="dropdown-item" href="#">Link 1</a>
          <a class="dropdown-item" href="#">Link 2</a>
          <a class="dropdown-item" href="#">Link 3</a>
        </div>
      </li>
    </ul>

    <form class="d-flex">
      <input class="form-control me-2" type="text" placeholder="Search">
      <button class="btn btn-primary" type="button">Search</button>
    </form>

    <ul class="navbar-nav ms-auto">
      <li class="nav-item">
        <a class="nav-link" href="#">登录</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">注册</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">联系我们</a>
      </li>
      <!-- Dropdown -->
      <li class="nav-item dropdown">
        <a class="nav-link dropdown-toggle" href="#" id="navbardrop" data-bs-toggle="dropdown">
          Dropdown link
        </a>
        <div class="dropdown-menu">
          <a class="dropdown-item" href="#">Link 1</a>
          <a class="dropdown-item" href="#">Link 2</a>
          <a class="dropdown-item" href="#">Link 3</a>
        </div>
      </li>
    </ul>

  </div>
</nav>